nut-debian/drivers/dstate.c
2016-07-18 02:11:41 +02:00

927 lines
18 KiB
C

/* dstate.c - Network UPS Tools driver-side state management
Copyright (C)
2003 Russell Kroll <rkroll@exploits.org>
2008 Arjen de Korte <adkorte-guest@alioth.debian.org>
2012 Arnaud Quette <arnaud.quette@free.fr>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdio.h>
#include <stdarg.h>
#include <sys/stat.h>
#include <pwd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include "common.h"
#include "dstate.h"
#include "state.h"
#include "parseconf.h"
static int sockfd = -1, stale = 1, alarm_active = 0, ignorelb = 0;
static char *sockfn = NULL;
static char status_buf[ST_MAX_VALUE_LEN], alarm_buf[LARGEBUF];
static st_tree_t *dtree_root = NULL;
static conn_t *connhead = NULL;
static cmdlist_t *cmdhead = NULL;
struct ups_handler upsh;
/* this may be a frequent stumbling point for new users, so be verbose here */
static void sock_fail(const char *fn)
{
int sockerr;
struct passwd *user;
/* save this so it doesn't get overwritten */
sockerr = errno;
/* dispense with the usual upslog stuff since we have stderr here */
printf("\nFatal error: unable to create listener socket\n\n");
printf("bind %s failed: %s\n", fn, strerror(sockerr));
user = getpwuid(getuid());
if (!user) {
fatal_with_errno(EXIT_FAILURE, "getpwuid");
}
/* deal with some common problems */
switch (errno)
{
case EACCES:
printf("\nCurrent user: %s (UID %d)\n\n",
user->pw_name, (int)user->pw_uid);
printf("Things to try:\n\n");
printf(" - set different owners or permissions on %s\n\n",
dflt_statepath());
printf(" - run this as some other user "
"(try -u <username>)\n");
break;
case ENOENT:
printf("\nThings to try:\n\n");
printf(" - mkdir %s\n", dflt_statepath());
break;
case ENOTDIR:
printf("\nThings to try:\n\n");
printf(" - rm %s\n\n", dflt_statepath());
printf(" - mkdir %s\n", dflt_statepath());
break;
}
/*
* there - that wasn't so bad. every helpful line of code here
* prevents one more "help me" mail to the list a year from now
*/
printf("\n");
fatalx(EXIT_FAILURE, "Exiting.");
}
static int sock_open(const char *fn)
{
int ret, fd;
struct sockaddr_un ssaddr;
fd = socket(AF_UNIX, SOCK_STREAM, 0);
if (fd < 0) {
fatal_with_errno(EXIT_FAILURE, "Can't create a unix domain socket");
}
/* keep this around for the unlink() when exiting */
sockfn = xstrdup(fn);
ssaddr.sun_family = AF_UNIX;
snprintf(ssaddr.sun_path, sizeof(ssaddr.sun_path), "%s", sockfn);
unlink(sockfn);
/* group gets access so upsd can be a different user but same group */
umask(0007);
ret = bind(fd, (struct sockaddr *) &ssaddr, sizeof ssaddr);
if (ret < 0) {
sock_fail(sockfn);
}
ret = chmod(sockfn, 0660);
if (ret < 0) {
fatal_with_errno(EXIT_FAILURE, "chmod(%s, 0660) failed", sockfn);
}
ret = listen(fd, DS_LISTEN_BACKLOG);
if (ret < 0) {
fatal_with_errno(EXIT_FAILURE, "listen(%d, %d) failed", fd, DS_LISTEN_BACKLOG);
}
return fd;
}
static void sock_disconnect(conn_t *conn)
{
close(conn->fd);
pconf_finish(&conn->ctx);
if (conn->prev) {
conn->prev->next = conn->next;
} else {
connhead = conn->next;
}
if (conn->next) {
conn->next->prev = conn->prev;
} else {
/* conntail = conn->prev; */
}
free(conn);
}
static void send_to_all(const char *fmt, ...)
{
int ret;
char buf[ST_SOCK_BUF_LEN];
va_list ap;
conn_t *conn, *cnext;
va_start(ap, fmt);
ret = vsnprintf(buf, sizeof(buf), fmt, ap);
va_end(ap);
if (ret < 1) {
upsdebugx(2, "%s: nothing to write", __func__);
return;
}
upsdebugx(5, "%s: %.*s", __func__, ret-1, buf);
for (conn = connhead; conn; conn = cnext) {
cnext = conn->next;
ret = write(conn->fd, buf, strlen(buf));
if (ret != (int)strlen(buf)) {
upsdebugx(1, "write %d bytes to socket %d failed", (int)strlen(buf), conn->fd);
sock_disconnect(conn);
}
}
}
static int send_to_one(conn_t *conn, const char *fmt, ...)
{
int ret;
va_list ap;
char buf[ST_SOCK_BUF_LEN];
va_start(ap, fmt);
ret = vsnprintf(buf, sizeof(buf), fmt, ap);
va_end(ap);
if (ret < 1) {
upsdebugx(2, "%s: nothing to write", __func__);
return 1;
}
upsdebugx(5, "%s: %.*s", __func__, ret-1, buf);
ret = write(conn->fd, buf, strlen(buf));
if (ret != (int)strlen(buf)) {
upsdebugx(1, "write %d bytes to socket %d failed", (int)strlen(buf), conn->fd);
sock_disconnect(conn);
return 0; /* failed */
}
return 1; /* OK */
}
static void sock_connect(int sock)
{
int fd, ret;
conn_t *conn;
struct sockaddr_un sa;
#if defined(__hpux) && !defined(_XOPEN_SOURCE_EXTENDED)
int salen;
#else
socklen_t salen;
#endif
salen = sizeof(sa);
fd = accept(sock, (struct sockaddr *) &sa, &salen);
if (fd < 0) {
upslog_with_errno(LOG_ERR, "accept on unix fd failed");
return;
}
/* enable nonblocking I/O */
if (!do_synchronous) {
ret = fcntl(fd, F_GETFL, 0);
if (ret < 0) {
upslog_with_errno(LOG_ERR, "fcntl get on unix fd failed");
close(fd);
return;
}
ret = fcntl(fd, F_SETFL, ret | O_NDELAY);
if (ret < 0) {
upslog_with_errno(LOG_ERR, "fcntl set O_NDELAY on unix fd failed");
close(fd);
return;
}
}
conn = xcalloc(1, sizeof(*conn));
conn->fd = fd;
pconf_init(&conn->ctx, NULL);
if (connhead) {
conn->next = connhead;
connhead->prev = conn;
}
connhead = conn;
upsdebugx(3, "new connection on fd %d", fd);
}
static int st_tree_dump_conn(st_tree_t *node, conn_t *conn)
{
int ret;
enum_t *etmp;
range_t *rtmp;
if (!node) {
return 1; /* not an error */
}
if (node->left) {
ret = st_tree_dump_conn(node->left, conn);
if (!ret) {
return 0; /* write failed in the child */
}
}
if (!send_to_one(conn, "SETINFO %s \"%s\"\n", node->var, node->val)) {
return 0; /* write failed, bail out */
}
/* send any enums */
for (etmp = node->enum_list; etmp; etmp = etmp->next) {
if (!send_to_one(conn, "ADDENUM %s \"%s\"\n", node->var, etmp->val)) {
return 0;
}
}
/* send any ranges */
for (rtmp = node->range_list; rtmp; rtmp = rtmp->next) {
if (!send_to_one(conn, "ADDRANGE %s %i %i\n", node->var, rtmp->min, rtmp->max)) {
return 0;
}
}
/* provide any auxiliary data */
if (node->aux) {
if (!send_to_one(conn, "SETAUX %s %d\n", node->var, node->aux)) {
return 0;
}
}
/* finally report any flags */
if (node->flags) {
char flist[SMALLBUF];
/* build the list */
snprintf(flist, sizeof(flist), "%s", node->var);
if (node->flags & ST_FLAG_RW) {
snprintfcat(flist, sizeof(flist), " RW");
}
if (node->flags & ST_FLAG_STRING) {
snprintfcat(flist, sizeof(flist), " STRING");
}
if (!send_to_one(conn, "SETFLAGS %s\n", flist)) {
return 0;
}
}
if (node->right) {
return st_tree_dump_conn(node->right, conn);
}
return 1; /* everything's OK here ... */
}
static int cmd_dump_conn(conn_t *conn)
{
cmdlist_t *cmd;
for (cmd = cmdhead; cmd; cmd = cmd->next) {
if (!send_to_one(conn, "ADDCMD %s\n", cmd->name)) {
return 0;
}
}
return 1;
}
static int sock_arg(conn_t *conn, int numarg, char **arg)
{
if (numarg < 1) {
return 0;
}
if (!strcasecmp(arg[0], "DUMPALL")) {
/* first thing: the staleness flag */
if ((stale == 1) && !send_to_one(conn, "DATASTALE\n")) {
return 1;
}
if (!st_tree_dump_conn(dtree_root, conn)) {
return 1;
}
if (!cmd_dump_conn(conn)) {
return 1;
}
if ((stale == 0) && !send_to_one(conn, "DATAOK\n")) {
return 1;
}
send_to_one(conn, "DUMPDONE\n");
return 1;
}
if (!strcasecmp(arg[0], "PING")) {
send_to_one(conn, "PONG\n");
return 1;
}
if (numarg < 2) {
return 0;
}
/* INSTCMD <cmdname> [<value>]*/
if (!strcasecmp(arg[0], "INSTCMD")) {
/* try the new handler first if present */
if (upsh.instcmd) {
if (numarg > 2) {
upsh.instcmd(arg[1], arg[2]);
return 1;
}
upsh.instcmd(arg[1], NULL);
return 1;
}
upslogx(LOG_NOTICE, "Got INSTCMD, but driver lacks a handler");
return 1;
}
if (numarg < 3) {
return 0;
}
/* SET <var> <value> */
if (!strcasecmp(arg[0], "SET")) {
/* try the new handler first if present */
if (upsh.setvar) {
upsh.setvar(arg[1], arg[2]);
return 1;
}
upslogx(LOG_NOTICE, "Got SET, but driver lacks a handler");
return 1;
}
/* unknown */
return 0;
}
static void sock_read(conn_t *conn)
{
int i, ret;
char buf[SMALLBUF];
ret = read(conn->fd, buf, sizeof(buf));
if (ret < 0) {
switch(errno)
{
case EINTR:
case EAGAIN:
return;
default:
sock_disconnect(conn);
return;
}
}
for (i = 0; i < ret; i++) {
switch(pconf_char(&conn->ctx, buf[i]))
{
case 0: /* nothing to parse yet */
continue;
case 1: /* try to use it, and complain about unknown commands */
if (!sock_arg(conn, conn->ctx.numargs, conn->ctx.arglist)) {
size_t arg;
upslogx(LOG_INFO, "Unknown command on socket: ");
for (arg = 0; arg < conn->ctx.numargs; arg++) {
upslogx(LOG_INFO, "arg %d: %s", (int)arg, conn->ctx.arglist[arg]);
}
}
continue;
default: /* nothing parsed */
upslogx(LOG_NOTICE, "Parse error on sock: %s", conn->ctx.errmsg);
return;
}
}
}
static void sock_close(void)
{
conn_t *conn, *cnext;
if (sockfd != -1) {
close(sockfd);
sockfd = -1;
if (sockfn) {
unlink(sockfn);
free(sockfn);
sockfn = NULL;
}
}
for (conn = connhead; conn; conn = cnext) {
cnext = conn->next;
sock_disconnect(conn);
}
connhead = NULL;
/* conntail = NULL; */
}
/* interface */
void dstate_init(const char *prog, const char *devname)
{
char sockname[SMALLBUF];
/* do this here for now */
signal(SIGPIPE, SIG_IGN);
if (devname) {
snprintf(sockname, sizeof(sockname), "%s/%s-%s", dflt_statepath(), prog, devname);
} else {
snprintf(sockname, sizeof(sockname), "%s/%s", dflt_statepath(), prog);
}
sockfd = sock_open(sockname);
upsdebugx(2, "dstate_init: sock %s open on fd %d", sockname, sockfd);
}
/* returns 1 if timeout expired or data is available on UPS fd, 0 otherwise */
int dstate_poll_fds(struct timeval timeout, int extrafd)
{
int ret, maxfd, overrun = 0;
fd_set rfds;
struct timeval now;
conn_t *conn, *cnext;
FD_ZERO(&rfds);
FD_SET(sockfd, &rfds);
maxfd = sockfd;
if (extrafd != -1) {
FD_SET(extrafd, &rfds);
if (extrafd > maxfd) {
maxfd = extrafd;
}
}
for (conn = connhead; conn; conn = conn->next) {
FD_SET(conn->fd, &rfds);
if (conn->fd > maxfd) {
maxfd = conn->fd;
}
}
gettimeofday(&now, NULL);
/* number of microseconds should always be positive */
if (timeout.tv_usec < now.tv_usec) {
timeout.tv_sec -= 1;
timeout.tv_usec += 1000000;
}
if (timeout.tv_sec < now.tv_sec) {
timeout.tv_sec = 0;
timeout.tv_usec = 0;
overrun = 1; /* no time left */
} else {
timeout.tv_sec -= now.tv_sec;
timeout.tv_usec -= now.tv_usec;
}
ret = select(maxfd + 1, &rfds, NULL, NULL, &timeout);
if (ret == 0) {
return 1; /* timer expired */
}
if (ret < 0) {
switch (errno)
{
case EINTR:
case EAGAIN:
/* ignore interruptions from signals */
break;
default:
upslog_with_errno(LOG_ERR, "select unix sockets failed");
}
return overrun;
}
if (FD_ISSET(sockfd, &rfds)) {
sock_connect(sockfd);
}
for (conn = connhead; conn; conn = cnext) {
cnext = conn->next;
if (FD_ISSET(conn->fd, &rfds)) {
sock_read(conn);
}
}
/* tell the caller if that fd woke up */
if ((extrafd != -1) && (FD_ISSET(extrafd, &rfds))) {
return 1;
}
return overrun;
}
int dstate_setinfo(const char *var, const char *fmt, ...)
{
int ret;
char value[ST_MAX_VALUE_LEN];
va_list ap;
va_start(ap, fmt);
vsnprintf(value, sizeof(value), fmt, ap);
va_end(ap);
ret = state_setinfo(&dtree_root, var, value);
if (ret == 1) {
send_to_all("SETINFO %s \"%s\"\n", var, value);
}
return ret;
}
int dstate_addenum(const char *var, const char *fmt, ...)
{
int ret;
char value[ST_MAX_VALUE_LEN];
va_list ap;
va_start(ap, fmt);
vsnprintf(value, sizeof(value), fmt, ap);
va_end(ap);
ret = state_addenum(dtree_root, var, value);
if (ret == 1) {
send_to_all("ADDENUM %s \"%s\"\n", var, value);
}
return ret;
}
int dstate_addrange(const char *var, const int min, const int max)
{
int ret;
ret = state_addrange(dtree_root, var, min, max);
if (ret == 1) {
send_to_all("ADDRANGE %s %i %i\n", var, min, max);
}
return ret;
}
void dstate_setflags(const char *var, int flags)
{
st_tree_t *sttmp;
char flist[SMALLBUF];
/* find the dtree node for var */
sttmp = state_tree_find(dtree_root, var);
if (!sttmp) {
upslogx(LOG_ERR, "%s: base variable (%s) does not exist", __func__, var);
return;
}
if (sttmp->flags & ST_FLAG_IMMUTABLE) {
upslogx(LOG_WARNING, "%s: base variable (%s) is immutable", __func__, var);
return;
}
if (sttmp->flags == flags) {
return; /* no change */
}
sttmp->flags = flags;
/* build the list */
snprintf(flist, sizeof(flist), "%s", var);
if (flags & ST_FLAG_RW) {
snprintfcat(flist, sizeof(flist), " RW");
}
if (flags & ST_FLAG_STRING) {
snprintfcat(flist, sizeof(flist), " STRING");
}
/* update listeners */
send_to_all("SETFLAGS %s\n", flist);
}
void dstate_setaux(const char *var, int aux)
{
st_tree_t *sttmp;
/* find the dtree node for var */
sttmp = state_tree_find(dtree_root, var);
if (!sttmp) {
upslogx(LOG_ERR, "dstate_setaux: base variable (%s) does not exist", var);
return;
}
if (sttmp->aux == aux) {
return; /* no change */
}
sttmp->aux = aux;
/* update listeners */
send_to_all("SETAUX %s %d\n", var, aux);
}
const char *dstate_getinfo(const char *var)
{
return state_getinfo(dtree_root, var);
}
void dstate_addcmd(const char *cmdname)
{
int ret;
ret = state_addcmd(&cmdhead, cmdname);
/* update listeners */
if (ret == 1) {
send_to_all("ADDCMD %s\n", cmdname);
}
}
int dstate_delinfo(const char *var)
{
int ret;
ret = state_delinfo(&dtree_root, var);
/* update listeners */
if (ret == 1) {
send_to_all("DELINFO %s\n", var);
}
return ret;
}
int dstate_delenum(const char *var, const char *val)
{
int ret;
ret = state_delenum(dtree_root, var, val);
/* update listeners */
if (ret == 1) {
send_to_all("DELENUM %s \"%s\"\n", var, val);
}
return ret;
}
int dstate_delrange(const char *var, const int min, const int max)
{
int ret;
ret = state_delrange(dtree_root, var, min, max);
/* update listeners */
if (ret == 1) {
send_to_all("DELRANGE %s \"%i %i\"\n", var, min, max);
}
return ret;
}
int dstate_delcmd(const char *cmd)
{
int ret;
ret = state_delcmd(&cmdhead, cmd);
/* update listeners */
if (ret == 1) {
send_to_all("DELCMD %s\n", cmd);
}
return ret;
}
void dstate_free(void)
{
state_infofree(dtree_root);
dtree_root = NULL;
state_cmdfree(cmdhead);
cmdhead = NULL;
sock_close();
}
const st_tree_t *dstate_getroot(void)
{
return dtree_root;
}
const cmdlist_t *dstate_getcmdlist(void)
{
return cmdhead;
}
void dstate_dataok(void)
{
if (stale == 1) {
stale = 0;
send_to_all("DATAOK\n");
}
}
void dstate_datastale(void)
{
if (stale == 0) {
stale = 1;
send_to_all("DATASTALE\n");
}
}
int dstate_is_stale(void)
{
return stale;
}
/* ups.status management functions - reducing duplication in the drivers */
/* clean out the temp space for a new pass */
void status_init(void)
{
if (dstate_getinfo("driver.flag.ignorelb")) {
ignorelb = 1;
}
memset(status_buf, 0, sizeof(status_buf));
}
/* add a status element */
void status_set(const char *buf)
{
if (ignorelb && !strcasecmp(buf, "LB")) {
upsdebugx(2, "%s: ignoring LB flag from device", __func__);
return;
}
/* separate with a space if multiple elements are present */
if (strlen(status_buf) > 0) {
snprintfcat(status_buf, sizeof(status_buf), " %s", buf);
} else {
snprintfcat(status_buf, sizeof(status_buf), "%s", buf);
}
}
/* write the status_buf into the externally visible dstate storage */
void status_commit(void)
{
while (ignorelb) {
const char *val, *low;
val = dstate_getinfo("battery.charge");
low = dstate_getinfo("battery.charge.low");
if (val && low && (strtol(val, NULL, 10) < strtol(low, NULL, 10))) {
snprintfcat(status_buf, sizeof(status_buf), " LB");
upsdebugx(2, "%s: appending LB flag [charge '%s' below '%s']", __func__, val, low);
break;
}
val = dstate_getinfo("battery.runtime");
low = dstate_getinfo("battery.runtime.low");
if (val && low && (strtol(val, NULL, 10) < strtol(low, NULL, 10))) {
snprintfcat(status_buf, sizeof(status_buf), " LB");
upsdebugx(2, "%s: appending LB flag [runtime '%s' below '%s']", __func__, val, low);
break;
}
/* LB condition not detected */
break;
}
if (alarm_active) {
dstate_setinfo("ups.status", "ALARM %s", status_buf);
} else {
dstate_setinfo("ups.status", "%s", status_buf);
}
}
/* similar handlers for ups.alarm */
void alarm_init(void)
{
memset(alarm_buf, 0, sizeof(alarm_buf));
}
void alarm_set(const char *buf)
{
if (strlen(alarm_buf) > 0) {
snprintfcat(alarm_buf, sizeof(alarm_buf), " %s", buf);
} else {
snprintfcat(alarm_buf, sizeof(alarm_buf), "%s", buf);
}
}
/* write the status_buf into the info array */
void alarm_commit(void)
{
if (strlen(alarm_buf) > 0) {
dstate_setinfo("ups.alarm", "%s", alarm_buf);
alarm_active = 1;
} else {
dstate_delinfo("ups.alarm");
alarm_active = 0;
}
}